Hi great members,
I've a question that never been answered. I'd like to use DTMF decoder with 8870 chip but before I order it globally, I tested normal calls between cellphones and no DTMF detected and after some research I got that mobile network is transmitting DTMF as digital signals...
I am attempting to make a circuit with the KT3170 chip. Outputs from chip sent to Arduino pin. Arduino will receive 4 numbers and display them on the LCD screen. It's working
But sometimes the Arduino will take the value from a number 2 times.
Like I dial 1 . Arduino will receive a 11 .
I...